Circuit breaker



-.Ma r. 3. 1925. 1,528,199

wf s. EVANS CIRCUIT BREAKER FiledJn. 16, 1922 2 Sheets-Sheet l Mar; 3. 1925.

W. S. EVANS CIRCUIT BREAKER '2 Sheets-Sheet' 2 Filed Jan. I 16, 1922 Patented Mar. 3, 1925.

UNITED I STATES WILLIAM S. EVANS, OF DULU'TH, MINNESOTA.

CIRCUIT BREAKER Application filed January 1,6, 1922. Serial No. 529,501.

i Minnesota, have invented certain new and useful Improvements in Circuit Breakers, of which the Jfollowing is a specification, reference being had therein to the accompanying drawing.

This invention relates to an electric cir- -cuit breaker and has special reference to a combination fuse and automatic circuit breaker or throw out switch for a multiple electric circuit.

The principal object is to produce a practical automatic throw out for multiple switches controlled by the action of a fuse in any one of the switches of a multiple circuit whereby when any one of the fuses is blown all of the cooperatively connected switches in the circuit will be acted upon simultaneously.

Other objects and advantages of themvention will be apparent in the further description thereof.

Referring now to the accompanying drawings forming part of this application and 1n which like reference characters indicate like arts: p Figure 1 is a front elevation' of two upri ht pivotally mounted electric switches; igure 2 is an enlarged sectional view on the line 2-2 Figure 3, and

Figure 3 is an enlarged vertical sectional view of one of the switches on the line '3-3, Figure 1.

1 and 2 represent the terminals of one of the electric circuits, they being supported on suitable porcelain or like insulators 3. The upper one of these` terminals terminates in the usual bifurcated contact 4 intermediate of which the contact blade 5 of the tubular upright 6 is frictionally engaged. The blade 5 has formed integral therewith the hub portion 7 which surrounds the tubular member 6 and is held thereupon by suitable screws, one of which is illustrated at 8 and extends within the tubular member and acts as a clamping and contact member to the upper end of the fuse 9.

The tubular member v6 is of insulating material and may be any len h desired for a convenient throw-out switc The lower end of this member terminates in the exter-z.

end of which is also screw threaded externally and slightly reduced in diameter as at 12, it being screw threaded within the upper end of the cylinder 13.

This cylinder is formed integral with its bifurcated supporting portion indicated at 14 which is mounted upon the short pin or shaft 15 mounted transverse the outwardly extending bracket 16 which is an integral portion of the contact72. The bracket 16 forms a sort of housing comprising two outwardly and upwardly extending spaced side walls, both of which are indicated by the numeral 16, and a covering or topwall 17, the outermost combined extremities of the side walls carrying therein the pin or shaft 15 as before described.

Through the side walls of the bracket 16, above and slightly inwardly of the u pin 15, 1s rotatably journalled the trigger s aft 18 which is of any desired length for cooperatively connecting two or more of the switches as indicated in Figure 1 .of the drawings. An arcuately shaped trigger 19 is rigidly fixed upon the shaft 18, one for each switch, and intermediate of the'walls of the bracket 16. The hub portion `oi each trigger is of an eccentric or cam like shape as at 20 for the purpose of engaging the dog 21 pivoted within the bracket as at 22, and the free end of which engages the transverse pin 23 intermediate of the lugs 24: formed integral with the back side of the cylinder 13.

A leaf spring 25 is attached as at 26 to the underside of the top wall 17 of the bracket and bears against the back of the dog 21 to cause it to normally remain in its lowermost position for convenient automatic engagement with the pin 23 when the cyliiider 13 is in its upright position, and the dog 21 is also provided with a depending portion 27 to keep it from dropping below the proper level and such engagement, as is obvious. tubular portion for holding it in upright position with the blade 5 in engagement with the contact member 4, or in other words, closed.

About the pin of Shaft 15 which pia otally supports the cylinder and its attachments is a double wire spring 28 rigidly fixed as at'29 at lits lowermost end to the outer lower face of the 4bracket 16 and its two The cylinder 13 is attached to the uppermost extremities spaced apart and entering thefinner walls of the bifurcated A supporting portionv 14: of the cylinder, as at 30. This spring is so tensioned as to normally hold the cylinder with its cooperative parts away from engagement with the dog 2l, or in its open position so that at any time when the dog 21 is disengaged from the in 23, as for example by the rocking of t e shaft 18 when the cam 20 of the trigger 19 willv cause such disengagement, the switch will immediately fly open by the action of the spring 28.

Within the cylinder 13 is mounted the piston 22, it being provided with a stem 33 which extends downwardly through a suitable hole in the center of the cylinder and which stem is for engagement with the trigger 19. The piston 22 is held normally, in

its uppermost position with its stem free from"l engagement with the trigger 19 by a suitable expansive spiral spring 34 about said stem, and there' are air escape passages Vor holes formed both in the lower end of the cylinder 13 as at 35 and in the side walls thereof as at 36, the latter being spaced upwardly from the lower end of the cylinder so that when the piston is forced to its lowermost position in the cylinder, escape of air or gases will readily take place therethrough.

As a rain. shield' or protecting hood over the bracket 2 and the operative parts, mounted thereupon, I have sho'wn a fiber or other form of suitable hood indicated at 31, the

same having a hole in the upper portion thereof through which the reduced portion 12 of the coupling 11 may be applied to the cylinder thus being made to pinch the hood 31 tightly between the cylinder and the coupling and there securely hold said hood at all times covering the otherwise exposed parts of the bracket when the switch is either opened or closed.

The lowermost end of the fuse 9, which extends longitudinally within the tubev 6, is attached as at 37 tothe inside of the coupling l1 and may be so attached prior to the placing of the tube 6 thereover when'the uppermost connection or screw 8 is applied completing the electric connection, and it is evident that this connection may be accomplished in any other desired manner without departing from the spirit .of the invention.

Now when two or more of such switches are assembled as lpreviously described and closed the novel functioning of the device will take place as follows:

If for some reason.common to such devices any one of the fuses 9 is blown, instant atmospheric expansion takes place within the hollow tube 6 and it being open 4downwardly into the cylinder 13, such expansion will obviously affect the piston 22 and force it downwardly within the cylinder, thus causing the stem 33 of the piston to impinge 2 against the trigger 19 and depressit which will cause the shaft 18 to rotate slightly resulting in all of the cams 20 upon said shaft engaging their respective triggers 21 and lifting them from holding Contact with thc pins 23 carried by the cylinders 13. This will permit as is obvious all of said cylinders withY their respective upright tubular arms being thrown open' by the action of their respective springs 28, as previously described, resulting in instant opening of all of the switches engaged with the trigger shaft.

The upper end of the tubular member 6 is closed bv a suitable removable plug 38 below which are laterally. formed holes 39 to permit of the escape of gases as well as excessive pressure when a fuse is blown, as it is found in practice that such escape does not interfere with the functioning of the device.

The relation of the trigger 19 on the shaft 18 to the bottom of the cylinder 13 is such that when the switch is thrown to its extreme open position, the outer portion of the bottom of the cylinder 13 intermediate of its bifurcated support 14 will engage and rest upon the uppermost extremity of the trigger, and which latter when fully depressed will rest upon the arched terminal 40. There is a double purpose in this engagement of the bottom of the cylinder witlh the trigger 19 in that in the event of the blowing of a fuse not being quite successful enough to Sufciently rock the shaft which transmits motion to the other cooperative switches, the falling of the switch in which the fuse was blown and its subsequent engagement with the trigger 19- will further rock the trigger shaft to insure its releasing all of the other switches.

While I have referred to the trigger shaft as a single unit, it will be understood that the metal portion thereof extends but a short distance from either side of each terminal and carries upon the ends thereof a couplin socket 1n its outer face into which the squared end 42 of the insulated portion 43 of the shaft lits, and the latter may be a comparatively loose fit to provide against inequalities of alignment of the 'shaft which might otherwise interfere with the success` ful operation o f same.

Having thus described my invention, what I claim and desire to secure by Letters Patent, is:

1. An electric switch of the type described, operable by the percussion of a blowing fuse, including a plurality of pivotally mounted fuse containing cylinders, and a rockable trigger shaft common to said cylinders.

2. An electric switch of the type described comprising a pluralityof spaced pivotally mounted cylinders, the free ends of each of said cylinders'carrying one terminal of a hub 41 provided with a squarel knife blade switch, a rockable trigger shaft lease ,the retaining means of each switch mounted'adjacent the pivotal mountings of simultaneously and open same.- the cylinders and common thereto, means In testimony whereof I hereunto aix my adacent the pivotal mountings of each cyl'- signature in the presence of two witnesses. in er for normally retaining same with its switch terminal closed, a fuse within each WILLIAM S' EVANS- cylinder, and means within each cylinder op- Witnesses: erable by the percussion of a blowing fuse" S. C. BRoNsoN,

whereby the trlgger shaft is operated to re- S. Gmo. STEVENS. 

